Almond × peach hybrid rootstock tree (Hansen 2168)

ABSTRACT

An almond × peach hybrid rootstock tree which is large, vigorous, upright to vase-shaped with medium trunk and branches, and peach-like in appearance; densely foliated with large, thin, smooth, medium green leaves on vigorous shoots and medium size on spurs; the leaves having a crenate-serrate margin, medium length petiole, and usually reniform glands; blooms from half-hardy, medium size, plump, pubescent flower buds; the flowers being large and conspicuous with large, ovate petals slightly pink in bud but becoming white when open; and is a productive bearer of ovate, white-fleshed fruit (not useful to the clone) having a peach-like, reddish-brown, very hard stone with large ridges; the tree root system being adventitious and deep rooting with uniformly emerging roots which are large, straight, and outwardly and downwardly inclined.

BACKGROUND OF THE VARIETY Field of the Invention

The inventor, Carl J. Hansen, in the conduct of an extensive plantbreeding program, originated a substantial number of new and distinctplant varieties, and which included the present almond × peach hybridrootstock tree. Such plant breeding program was undertaken by inventor,Carl J. Hansen, in the research and experimental plant nursery andorchards of the Department of Pomology at the University of California,Davis, Yolo County, Calif.

CLASSIFICATION OF THE VARIETY

The present variety of rootstock tree is embraced by Subclass 30,Plants, of the U.S. Patent Office Manual of Classification.

EXISTING VARIETIES

Among existing plant varieties known to inventor, Carl J. Hansen, andmentioned herein for the purpose of reference or comparison, are thefollowing:

Almond Tree ("Almond B"), an unpatented chance seedling selected from acommercial orchard located near Ballico, Merced County, Calif.; PeachTree ("Peach 1-8-2"), an unpatented selection of the Department ofPomology, University of California , Davis, Calif.;

Almond × Peach rootstock tree ("Hansen 536"), a selection of theDepartment of Pomology, University of California, Davis, Calif., and thesubject of co-pending U.S. plant patent application Ser. No. 408,715,filed Aug. 16, 1982; Almond tree ("Nonpareil"), unpatented; and Plumtree ("Marianna"), unpatented.

ORIGIN OF THE VARIETY

The present varity of almond × peach hybrid rootstock tree wasoriginated by inventor, Carl J. Hansen, in the aforesaid research andexperimental plant nursery and orchards, as a cross--by handpollination--between "Almond B" and "Peach 1-8-2", and was a selectionfrom a seedling population of said cross; the selection having been madeupon the ascertainment--under careful and continuing observation--thatthe present F₁ clone bore certain desirable characteristics for use as arootstock.

ASEXUAL REPRODUCTION OF THE VARIETY

Subsequent to its origination and selection, as above, the presentalmond × peach hybrid rootstock tree was successfully asexuallyreproduced by inventor, Carl J. Hansen, in the aforesaid research andexperimental plant nursery and orchards; the reproductions having beenaccomplished from hardwood cuttings, and, in maturity, in certain testplots in the aforesaid experimental orchards, said reproductions rantrue, in all respects, to the original tree of the present variety.Vegetative reproduction of the variety has also been successfullyaccomplished from softwood cuttings under mist, and by budding.

SUMMARY OF THE VARIETY

The present variety of almond × peach hybrid rootstock tree is large,vigorous, upright to vase-shaped with medium trunk and branches, andpeach-like in appearance; densely foliated with large, thin, smooth,medium green leaves on vigorous shoots and medium size on spurs; theleaves having a crenate-serrate margin, medium length petiole, andusually reniform glands; blooms from half-hardy, medium size, plump,pubescent flower buds; the flowers being large and conspicuous withlarge, ovate petals slightly pink in bud but becoming white when open;and is a productive bearer of ovate, white-fleshed fruit (not useful tothe clone) having a peach-like, reddish-brown, very hard stone withlarge ridges; the tree root system being adventitious and deep rootingwith uniformly emerging roots which are large, straight, and outwardlyand downwardly inclined.

The present variety of almond × peach hybrid rootstock tree is moreparticularly characterized as follows:

The present variety, as a rootstock, has high vigor and more so thanother rootstocks, such as almond or peach seedlings, or the Mariannaplum. Further, because of its high vigor, the present variety--as arootstock--is more tolerant to drought and growth in marginal soil; thisespecially in comaprison to peach seedlings and the Marianna plum, butprobably not almond seedlings.

Additionally, as a rootstock, the present variety is

(a) Immune to the two common forms of root-knot nematodes; to-wit,Meloidygyne incognita acrita and M. javanica;

(b) Although not wholly resistant to crown rot caused by excess waterand Phytopthora fungi, the present variety is more tolerant than manyother rootstock selections of hybrid populations tested;

(c) The present variety can be successfully reproduced, in highpercentages (75%-90%) by hardwood cuttings treated with hormones,fungicide, and planting in a nursery in the Fall of the year underCalifornia conditions;

(d) The deep rooting of the variety provides excellent anchorage of therootstock, better than the major rootstocks such as peach seedlings andthe Marianna plum;

(e) In comparison, the present variety generally resembles the tree ofthe clonal rootstock Hansen 536 in appearance, but is slightly morevigorous, roots more consistently, and differs in having tree branchesthat are more green with less red color of the developing leaves andshoots.

BRIEF DESCRIPTION OF THE DRAWING

The drawing is an illustration, by photographic reproduction in color,and in one view, of a tree of the variety; in another view, flowers ofthe variety; and, in a still further view, the root system out of groundand cut from the tree.

DESCRIPTION OF THE VARIETY

The botanical details of the present new and distinct variety of almond× peach hybrid rootstock tree--with color definitions in common colorterms--are as follows:

Tree:

Size.--Large.

Vigor.--Vigorous.

Form.--Upright to vase-shaped. Peach-like appearance, with a peach habitin that flowers are produced laterally on long, vigorous shoots.

Hardiness.--Half-hardy.

Productivity.--Tree bears large number of fruit which are not useful tothe clone.

Use.--Rootstock, primarily for almond and peach, but Japanese plum andprune varieties are compatible. Not compatible to apricot.

Root system.--Deep rooting. Uniformly emerging. Adventitious with large,straight, outwardly and downwardly inclined roots providing good treeanchorage. Roots develop readily on hardwood cuttings.

Trunk:

Size.--Medium.

Texture.--Smooth-barked.

Color.--Grayish brown that develops prominent vertical striations orfissures.

Branches:

Size.--Medium.

Texture.--Smooth-barked.

Color.--Brown. Newly developing shoots in Spring are green with slightlyreddish color. Young (one-year old) shoots are green with a reddishbrown overcolor on exposed upper surface. Older shoots becomebrown-gray.

Lenticels.--Numerous. Conspicuous. Horizontal.

Leaves:

Density.--Dense.

Size.--Large (medium on spurs). Average length -- 79 mm. (range 68 to 85mm.). Average width -- 28 mm. (range 25 to 30 mm.). Ratio of width tolength -- 1:2.8.

Thickness.--Thin.

Texture.--Smooth.

Color.--Medium green on vigorous shoots.

Margin.--Crenate-serrate.

Petiole.--Medium length. Average length -- 21 mm. Ratio petiole to blade-- 1:3.8.

Glands.--Usually reniform. Average number -- usually 2 to 3, sometimesnone, 1 or 4.

Flower buds:

Size.--Medium.

Hardiness.--Half-hardy.

Form.--Plump.

Pubescence.--Pubescent.

Flowers:

Blooming period.--Mid-February. About with or slightly earlier than theNonpareil almond.

Size.--Large. Average -- 35-40 mm. in diameter when fully open. Showy.

Peduncle.--Glabrous. Average length -- 3 mm.

Calyx.--Green overlaid with red.

Sepals.--Usually green inside. Glabrous at base, becoming pubescent atlobes and margins.

Petals.--Large. Slightly pink in bud, but becoming white when flowerfully open. Prominent red at base of petal, but fades with age. Averagesize -- 18×14 mm. Round-ovate, with very slight emarginate indentationon apical end.

Stamens.--Average size -- 8-14 mm, longer on outside. Light pink, fadingto white with age, but retaining pink at base.

Anthers.--Yellow.

Pistils.--Very straight. Pubescent. Some undeveloped.

Fruit:

Season of maturity.--Ripens in August.

Bearing.--Productive but non-useful. Borne on long shoots similar topeach.

Form.--Tends to be ovate and intermediate in structure between peach andalmond.

Flesh.--White. Red next to stone. Becomes soft and develops a suturewhich tends to split at maturity, but without separating completely fromstone.

Pubescence.--Skin highly pubescent.

Flavor.--Astringent.

Stone:

Form.--Peach-like in appearance.

Ridges.--Large. Very hard.

Color.--Reddish-brown.

Kernel.--Inedible.

Resistance to Insects and Diseases: Immune to root-knot nematodesMeloidygyne incognita acrita and M. javanica. Some tolerance to ironchlorosis.

The herein described almond × peach hybrid rootstock tree may vary inslight detail due to climatic and soil conditions under which thevariety may be grown; the present description being of the variety asgrown in the Central Valley of California.

It is claimed:
 1. A new and distinct variety of almond × peach hybridrootstock tree substantially as illustrated and described, particularlycharacterized by a high percentage of successful reproductions fromhardwood cuttings, by a deep rooting, adventitious root system providingexcellent anchorage, by immunity to root-knot nematode infections,Meloidygyne incognita acrita and M. javanica, and by a tree generallyresembling the Hansen 536 but slightly more vigorous, roots fromcuttings more consistently, and with tree branches which have more greenand less red color of the developing leaves and shoots.